Lubricating projectile



(No Model.) 2-Sheets-Sheet 1..

s. A. DAY.

LUBRIGATING PROJEGTILE.

' No. 407,890. 7 Patehted July-30, 18 9,

. INVENTOR: WITNE'SSES: MM Ln. Jew

- By his Attorneys, 4 M @W w (No Model.) 2Sheets-Sheet. 2.-

.DAY.

. LUBRIO GPROJEGTILE.

' O. 407,890. Patented July so, 1889,,

WITNESSES; INVENTOR:

By his A/zameys,

zen of the United States, residing in Bowling bodyportion through the basc,'imparts a con- UN Tnn STATES SELDEN A.

PATENT Quinton.)

'PROJEOTILE coMrAnY, on NEW roan, n. Y.

LUBRlCATlNG=PFlJECTlLE SPECIFICATION forming part of Letters Patent in. 407,890, dated July so, 1889.

Application filed March 6, 1889. Serial 1%. 302,175. on model.)

.To all whom it may conooritf Be it known that I, SELDEN A. DAY, aciti- Green, county of lVood, and Stateof Ohio, have invented certain new and useful Iniproveni'ents in Projectiles, of which the followingis a specification.

This invention relates to projectiles for firearms, including either small -arins or ordnance, the invention being applicable to bullets, solid shot, and explosive shells.

. My improved projectile is designed especially for use in fire-arms the bore of which is rifled in order to impart a rotary motion to the projectile during the act of firing.

The objects of my invention are to impart an accelerating rotary motion to the project ile, thereby overcoming its inertia gradually and accomplishing the purpose of an increasing-twist riiiing without incurring its disadvantages, and to provide for the more thorough -andeffective lubrication of the bore than has heretofore been accomplished. To this'end my improved projectile is constructed with abody portion of any suitable proportions anti: with a separate base or sabot connected to i it through the medium of a screw-thread and-normally partly unscrewed. The body of the projectileis formed of a mass, and consequently has an inertia greatly in excess of that of the base. The body of the projectile is made of slightly-smaller diameter than the bore of the gun, so that it shall rest upon the lands or spaces between the rifle-grooves, while the base or sabot is made of larger diameter or is formed with exterior ribs of any known pattern, so that it shall engage the rifie-grooves \Vhen'the projectile, with tlrdbase partly unscrewed, is placed in the rifled bore of the fire-arm and fired, the inertia of the body of the projectile causes it to resist the rotative tendency of the rifling, while the base being engaged by the rifles is rotated, and consequently is screwed up to the body portion, so that before the projectile leaves the gun the base'has been fully screwed up audits rotationiscoim mu'nicnted to the body of'the proj ectile: I The f iction of the screw-threads, increased by the propulsive pressure.transinitted to the tinuous rotative tendency to the body portion, which gradually becomes effective in .rotatin g the body portion as it overcomes the inertia thereof, so that the body of the -projectile during its travel through the bore of the gun receives an accelerating rotary motion, which with the best proportions should base or sabot at the instant that the latter becomes screwed tightly against the body, which should occur just before the emergence of the projectile from the gun, so that at the time of passing out of the bore the base and body are rotatingtogether at a uniform speed.

In a space or cavity between the partly-unscrewed base and the body a mass of lubricating substance is placed, which by itspresence further resists the screwing up of the base, and serves thus to impart a rotative tendency to the projectile body, and which serves the further purposeof lubricating the bore of the gun by being squeezed out thereinto by reason of the screwing up of the base. As this screwing up takes place continuously during the travel of the projectile through the bore, the squeezing out of the lubricant occurs also continuously, so that approximately a uniform quantity of lubricant is spread upon the surface of the bore during the entire travel of the projectile. The arrangement is such that the lubricant thus expelled is discharged inadvance of the base or sabot, and consequently enters between the latter and the rifle grooves and lands, so that the lubricant is applied at the exact time and place that it is needed, and each projectile the succeeding projectile.

l have shown in the accompanying drawlugs several different embodiments of my invcntion.

Figure l is a side elevation of a shell embodying my im ention. Fig. 2 is a longitudinal mid-section thereof. Fig. 2) is an end elevation thereof. th serew base removed. Fig. 5 is a fragmentary longitudinal section showing the base screwed up. Fig. (5 is a fragmentary elevation, partly in mid-section, showing slightlymodificd construction of the-screw-base. Figs. 7 and 8 show a modified construction designed nearly equal the speed of rotation of thelubricatcs the bore for itself instead of for Figl is a front elevation of IOO ' sabot.

- signed for purposes of penetration.

out upon its exterior.

Referring to the drawings, let A designate the body of the projectile, and B the screwbase or sabot. the greater portion of the weightof the entire projectile. The base B is united to the body A through'the medium of male and female screw-threads a, the sabot being normally partly unscrewed and the intervening space thus formed being filled with lubricating ma-' terial. (Designated at C and C.)-' The projectile body A is made of such small diameter that it is not engaged by the rifle-grooves, but rests upon the intervening lands. The base B is made of somewhat larger diameter, so that it enters the grooves, or is formed with ridges or projections which take the grooves. The base or exterior portion thereof which takes the rifle grooves is constructed by pref.- .erence of soft metal.

Having thus in general described my in vention without special reference to any one of the constructions shown, Iwill now proceed to describe more particularly the several different constructions illustrated in the accompanying drawings.

Figs. 1 to5, inclusive, illustrate a shell de- The rear portion of the projectile body A is formed with a neck ortail b,havingmale screw-threads a a The base B is formed as a screw-cap having in terior or female screwthreads adapted to screw upon this neck. The screw-threads should be of somewhat steep pitch, a double thread being preferably used. When the base is partly screwed on, two cavities or spaces are formed which are filled with lubricant, the one being the space within the cup against the end of the screwthreaded neck I), and the other the annular space or groove around the exterior of the neck I) and between the front edge orfiange of the, cup and the shoulder formed by the contraction of the neck. The latter of these spaces is filled with a mass of lubricant lettered C, while the former is filled with lubricant lettered C. The lubricant may be tallow or-any kind of grease, wax, or a mixture of tallow or wax with graphite, or it may consist of some absorbent material saturated with oil. The lubricant at C is preferably'a -mixture of tallow and graphite, or an absorbcnt-such as felt-saturated with oil, while that in the space 0 may be a mixture of tallow and graphite or any suitable grease .or wax alone. As the base B is screwed up The body A comprises by far by the action of the rifle-grooves in firing, the lubricant is squeezed out, that at C being delivered to the bore of the gun'just in front of the projecting portion or luting c of the base, which is preferably made of soft metal to enter the rifles,while the lubricant C is squeezed out through holes or openings cl (1. The base 13 is preferably constructed of hard metal,-in which the screw-thread is formed, and its outer or projecting portion 0 is a luting of soft metal applied to it in any suitable manneras, for example, in the manner shown in Fig. 2-where the tubular luting of soft metal comes against a shoulder near the front of the cup-shaped base. The soft-metal luting preferably projects beyond the'rear face of the head B in order to form a cup-packing to be expanded into the grooves by the gaseous pressure in firing on the principle of the expanding sabot of the Parrott shell. This construction of the base B, however, may be greatly varied, one example of which is shown in Fig. 6, where the entire base is formed of one piece of suitable metal screwing directly on the neck I), and formed with holes d d for the discharge of the lubricant. The lubricant, instead of being provided both at O and C, may be omitted in either one of these places. In Fig. 6 the lubricant is shown applied only at 0.

My invention is adapted not only to explosive shells and solid shot for ordnance,but'

also to bullets for small-arms.

Figs. 7 and 8 show a construction applicable to either large or small projectiles. The body A is formed with a screw-neck b, which is somewhat prolonged, and on which are screwed one or more nuts, we nuts B and B being shown. A lubricating -washer C is shown as interposed between these two nuts, and another Washer 0 between the nut 13 and the shoulder at the front of the screwthreaded neck. 7

The forward nut B may be of the same diameter as the bodyA, so that it will not take the rifle-grooves; but the rear nut B is provided with an exterior luting of soft metal 0, whereby it is constituted the screw-base or sabot before referred to, there being, however, this diiference between this base and that shown in the preceding figures, that it is not in the form of a cup since the screw-neck b projects entirely through it. The washers O C are preferably loose felt' saturated with oil or impregnated with grease or wax. WVhen the projectile is fired, the base B is first screwed up' by the riflin g, thereby forcing out the lubricant C, after which the nut B is screwed up, forcing out the lubricant C ,If

-lut ing c is preferably a cup-shaped piece of 4 of the base l ,-being designed to be of the the Parrott shell.

same diameter as the projectile body A, so.

that it shall not enter the rifle-grooves until expanded thereinto by the internal pressure of the gases, after the manner of the sabot of Such construction is well adapted for muzzle-loading guns. In Fig. 13

'the soft metal 0 is confined between two flanges or shouldersh and '1', while in Fig. 14 it rests against afiange 2' at the front, and is formed with a rabbet which conceals this flange.

My invention, by a portant practical advantage of impayting to the projectile an accelerating rotation without resorting to the expedient of riding the bore of the gun with an increasing or gain twist.' My projectile is designed to be fired in barrels having a rifiing of uniform twist.

T hc disadvantage of such rifiing heretofore has been that the inertia of the projectile usually causes it to resist at starting the rotative movement which the twist imparts, so that until this inertia is overcome it is'being forced forwardly through the bore with a slower rotative movement than that corresponding with the pitch of the riding, so that in this case the metal of the projectile is torn oif by being forced across the rifle-levels, thereby. injuring both the projectile and the gun. To overcome this obvious difficulty, the employment of anincreasing or gain twist has been resorted to, but with no very satisfactory results, such a twisfibeing found to have the disadvantages-that it tends'to rotate the front of the projectile at a more rapid speed than the rear portion thereof and that it twists and distorts the projectile in such way that it materially increases the friction in its passage through the bore. ,These difficulties have increased with the change that has taken place in the proportions of projectiles in the direction of an increase of theirlength in proportion to their caliber.

With my improved projectile the theoretical advantages of the increasing twist are realized in the use of a gun rifled with a uniform twist, since the inertia of the projectile is overcome gradually, the screw-base being Lof very little weight and affording, consequently, very slight inertia, being caused to partake immediately of.the rotary motion. due

to the pitch of the riding, and this motion being gradually communicated to the projectile body, By the use of my invention a riding of more rapid twist can be employed than has b en hitherto practicable. .This constitutes a important desideratum, in view of the siinple and inexpensive construction of the projectile, realizes theimpresent tendency toward the reduction of the caliber and the necessary increase of the length of the projectile, it being well known that the greater the length of a projectile in proportion to its caliber the more rapid revolution it requires to cause it to fly end on.

My invention also possesses very important advantages in the thorough and effective lubrication of the barrel, whereby the injury of the projectile in being fired is prevented and the undue heating of the barrel and the cutting .of the rifle grooves and lands are avoided;

The 'portionof my invention which relates to 'the lubrication may be omitted, while retaining the advantages inherent in the screwbase or sabot; but in such case it is preferable to substitute for the mass of lubricant some other similar resisting substance or device for communicating from the base to the projectile body the rotary tendency. This rotary movement may be communicated solely by the friction of the screw-threads, but it is preferable to make the screw-threads as nearly frictionless as possible and to substitute some sufficiently-resisting material or.

elelnentfor thus communicating the rotation.

I claim as my invention the following-defined novel features and combinations, substantially as hereinbefore specified, namely:

1. A projectile having aseparate base or sabot connected to it through the mediumof a screw-thread and normally partly unscrewed, said base being adapted to engage the riflegroovcs in firing and to be rotated thereby, and by reason of such rotation and the inertia of the body of the projectile to be" screwed up to the latter.

2. A projectile having a separate base or sabot connected to it through the niediumiof. a screw-thread and normally partly nu}; screwed, and with a partially-resisting sub stance or filling. between a shoulder or face on the front of said base, and a shoulder o face at the rear of the body of the projectileadapted to partially resist the screwing up of the base in the operationof firing-and by such resistance to communicate the rotarymovement of the base gradually-to the body' of the projectile in order to gradually overi ,come' the inertia of the latter and impart to it an accelerating rotation};

A projectile having a separate base sabot connected to it through the medium of a screw-thread and normally partly unscrewed, and .provided with a lubricating substance between said base and the body of the projectile adapted to be gradually squeezed outby the screwing up of the base during the operation of firing.

4. Aprojectile consisting of a body portion and a separate with a screw-threaded neck and the other with a screw-threaded socket engaging said ase or sabot, the one formed neck, a cavity formed Within'the socket and provided with holes extending from said cavity to the exterior, combined with a fillingof lubricating substance in said cavity,whereby itis adapted to be squeezed out through said holes by the screwing up 'of the base against the body portion of the projectile, and i'n'ea-ns for operating said base.

5. A projectile having its body portion formedwith a contracted screw-threaded neck at its rear, and a separate base formed with internal screw-threads screwing upon said neck, normally partly unscrewechand formed t-o'project beyond the diameter of the body my name in the pre's ence of two subscribingwitnesses. v v

' \S'ELDEN A. DAY.

Witnesses ARTHUR C. FRASER, .TNO.- E. GAVIN. 

